A new study from the University of Chicago Medicine reveals that people with alcohol use disorder (AUD) and depression experience high levels of stimulation and pleasure when intoxicated, similar to drinkers who do not have depression.
The findings counter the long-held belief that the pleasure people experience when drinking alcohol decreases with addiction and that drinking to intoxication is mainly to reduce negative feelings as a form of self-medication.
“We have this folklore that people drink excessively when they’re feeling depressed and that it’s really about self-medicating,” said Andrea King, PhD, Professor of Psychiatry and Behavioral Neuroscience at UChicago and lead author of the study. “In this study of natural environment drinking and smart phone-based reports of the effects of alcohol in real-time, participants with AUD and a depressive disorder reported feeling acute, sustained positive and rewarding alcohol effects — just like their non-depressed counterparts.”
Published February 1 in the American Journal of Psychiatry, the research challenges conventional notions about alcohol’s effects in depressed people who drink excessively and could improve treatment approaches by focusing medication and behavioral approaches more on alcohol’s pleasure reward pathways and less on stress-responsive systems.
“Currently, the focus of treatment is often on resolving stress and symptoms of depression, but that is only addressing one side of the coin if we don’t also address the heightened stimulation, liking and wanting more alcohol that occur in both depressed and non-depressed people with AUD,” said King, who has been conducting human research for decades to test responses to alcohol that lead to addiction.
The effects of alcohol on the brain are complex, and improved understanding of the factors that affect an individual’s vulnerability to AUD and depression is critical to identify and initiate early, effective treatment. However, few studies have examined how people with AUD respond to alcohol either in controlled laboratory settings or the natural environment; including individuals with AUD and another co-morbid diagnosis adds to the complexity.
The research followed 232 individuals across the U.S. between the ages of 21 to 35, corresponding to the period when most heavy drinking occurs in a person’s lifetime. Half of the study group met criteria for AUD in the past year and were evenly divided in terms of those who had or had not experienced a major depressive disorder in the past year. Individuals who had suicidal ideation were excluded for safety reasons, as were people who had severe alcohol withdrawal symptoms.
Through their smartphones, participants answered questions every half hour for three hours during one typical alcohol drinking episode and a non-alcohol episode. The researchers found that alcohol consumption reduced negative feelings, although the reduction was small and nonspecific to their depression or AUD status. The positive effects of alcohol were much higher in individuals with AUD than those without AUD and contrary to lore, similar in those with AUD and depression and those without depression.
“For nearly a decade, our group has been improving methods to use mobile technologies to measure real time clinically meaningful outcomes in people with AUD and those at risk for alcohol-related problems,” said study co-author Daniel Fridberg, PhD, Associate Professor of Psychiatry and Behavioral Neuroscience at UChicago. “These approaches allow us to bridge the gap between the lab and real life and have led to new insights that could one day result in better treatments.”
The study’s findings call into question the predominant theory that alcohol addiction arises from the brain’s attempt to maintain stability despite repeated heavy drinking. That theory describes a “dark side of addiction” where repeated heavy drinking over time leads to changes in the brain systems involved in stress and reward. As a result of those changes, it is hypothesized that individuals shift from drinking for pleasure to drinking to avoid withdrawal and stress.
King says this theory does not account for the high levels of stimulation and pleasure that she likens to an accelerator pedal fueling more dependency.
“As treatment providers, we’re taught people with AUD are drinking to self-medicate and feel better,” said King. “But what exactly are they feeling? From our study, it seems to be high levels of stimulation and pleasurable effects, with a modest decrease in negative states.”
King’s next study examines whether adults between 40 to 65 years old who have had AUD for decades also experience similar heightened feelings of pleasure when drinking versus older drinkers without AUD. The prevailing theory would suggest these individuals would show blunted positive responses and high levels of tolerance to alcohol. King will examine whether they show a long-term sensitivity to alcohol’s enjoyable effects, much like in this study of depressed drinkers.
